Well screen perforation cleaner



May 3, 1950 B. P. ARTERBURY ETAL wELL SCREEN PERFoRA'rIoN CLEANER Filed oct. 20, `1955 United States Patent O WELL SEN PERFORATION CLEANER Bryant P. Arterbury and George M. Clark, Houston, Tex., assignors of thirty-three and one-third percent t Roy L. Arterbury, Houston, Tex.

Application Getober 20, 1955, Serial No. 541,570

Claims. (Cl. 166-177) `This invention relates to tools as oil Well service tools termed `well screen perforation cleaners. Specifically, it relates to a tool which may be used to clean the screen or perforated section of' tubing which is interposed in the well casing n the region of the oil producing formation, this application being a continuation-in-part of copending patent application Serial Number 344,592, for Cleaning Tool, tiled in the United States Patent Office by Bryant, P. Arterbury and George M. Clark under tiling date of March 25, 1953 and issued April 3, 1956, as Patent No. 2,740,481.

It is an important object of this invention to provide a cleaning tool of this class having a packer assembly which may be used with a pipe or tubing string lowered into a cased well bore having a perforated casing, the tubing passing sealably through the casing. at the top of the well where means is provided to pump fluid into the casing below the seal to thereby pressurize and clean the perforations and adjacent formation as the packer assembly is manipulated to correlate the application of the pressurized fluid.

It is also an important object of this invention to employ such packer assembly on a tubing string in such a cased well bore as hereinabove described in a manner to test the pressure the casing will withstand above the perforated section. y

It is another and primary object of this invention to provide a packer assembly of the class described operable on a tubing string extending sealably through a lower perforated cased well bore into which pressurized fluid is introduced at the top below the seal to pressurize and also clean the perforations and adjacent formation through manipulation of the packer assembly.

It is also another primary object of this invention to provide a packer assembly of the class described operable on a tubing string in such a cased well bore in a manner to test the pressure the unperforated casing will withstand above the perforated lower portion.

It is yet another primary object of this invention to provide a packer assembly of the class described which is versatile of operation in such a well bore, and which is capable of operative adjustment, as by rotation.

Other and further objects of this invention will be apparent when the speciiication is considered in connection with the drawings in which:

Fig. 1 is a sectional elevation showing an embodiment of the invention as it is lowered on a pipe string into a well bore; and

Fig. 2 is a sectional elevation of the embodiment of Fig. 1 shown in position in the well bore and operative to clean a perforated section of casing.-

Referring in detail to the drawings, a mandrel body 11 is shown connectedto a pipe or tubing string-42 which extends within a cased well bore 40 to the top of the well. A closure 41 at the top of the casing 40 sealably encloses the tubing 4 2, as by the provision of O-rings 51 in the closure, and the tubing 4Z extends above the Patented May 3, 1960 closure to deliver fluid upwardly to conventional receiving means therefor.

The mandrel body 11 has a packer assembly 26 slidable thereon below a shoulder 55 on the mandrel body 11. Such assembly includes a sleeve 2'7 as the element providing this sliding contact. The lower part of the sleeve 27 provides an internal recess space 57 therein and radial ports 28 through the mandrel wall communicate with such recess. A retaining nut 31 is threaded onto the lower end of the sleve 27 and provides the retaining seat for a cup-type packer 29 which extends thereabove surrounding the sleeve 2.7 and in slightly spaced relation from the ports 28 thereon. Such sleeve 27' has longitudinal slots 44 therein and pins 45 extend across such slots at the upper and lower ends thereof to be supported in the walls defining such slots. Friction springs 43 have their ends connected to such pins 45 and are of a coniiguration to bear outwardly with substantial frictional engagement against the wall of the casing 40.

The retaining nut 31 is countersunk at its lower end to provide a valve seating surface or valve seat 59, and in the lowermost position of the packer assembly 26', such valve seat 59 seats against an inclined shoulder 32 provided by a mandrel part or valve element 56 of larger outer diameter than is the mandrel diameter immediately thereabove. A circumferential series of longitudinal ports 33 is provided in the part 56 to extend to the face of the shoulder 34, and when the nut 31 seats on the shoulder 32 uid communication may be established from the annular space surrounding the mandrel 11 above the packer 29, through the ports 28, the space 57, and the longitudinal ports 33, to the space surrounding the mandrel 11 below the packer 29. An annular relief valve 35 which slides on a turned down mandrel part 58 below the mandrel 56 is externally threaded to receive an adjustment nut 37 thereon, and a spring 36 bears downwardly on the upper face of the adjustment nut 37 and upwardly against the under falce of the relief valve 35 to bias the valve 35 normally to close the ports 33. A shoe 38 is threaded onto the end of the mandrel part 38 to guide the tool into the well and to protect the external threads on the part 58. As indicated diagrammatically in the drawings, conventional friction elements 46 are provided on the adjustment nut 37 to bear frictionally against the Wall of the casing 40. A pin 51 in the mandrel body 11 within the sleeve 27 extends through a well known J slot 51 shown in the sleeve 27 to effect positionings to be hereinafter described.

As shown in Fig. 1 the sleeve 27' -is maintained in the relative vertical position shown with relation -to the mandrel body 11 as the tool is lowered into the well bore by virtue of the frictional drag of the springs 43 maintaining the sleeve 27 in abutment at its top with `the mandrel body. In such position right handed or clockwise rotation of the mandrel body 11 with relation to the sleeve 27 as viewed from the top of the well, while the sleeve 27' is inhibited against rotation by the frictional engagement of the springs 43 with the casing 40, will result in the pin 51 in the mandrel body 11 moving to the end of the lower leg of the J-slot 52 after which the sleeve 27 and mandrel body 11 descend together in locked relation, or may be rotated together in right hand or clockwise direction as viewed from the top of the well. Y

In this position the operation of the pumpy 47 at the top of the well to deliver fluid through the pump discharge 48 and down the casing 40 results in Huid being pumped into the interior of the cup-like packer 29 and 4through the ports 28 and downwardly through the space between mandrel body 11' and sleeve 27 to pass down to the bottom of the tool and then upwardly through the' mandrel bore 13 to carry along therewith any sand which may have entered the casing 49 through perforations 53 therein, as from a sand formation 54.

This operation can be carried out as the tool is lowered or moved vertically since the packer 29 is not set by the pumping of uid through the interior thereof, and in this vertical movement the packer 29 may or may not frictionally engage the casing di), dependent in part upon the force with which the iluid is pumped. Thus the casing 40 may be washed at selective vertical positions.

When the tool reaches a vertical position where it may be `desired to wash extensively and also to wash the perforations 53 and the sand 54 externally of the casing 40, the mandrel body l1 is rotated in a counter-clockwise or yleft handed direction as viewed from the top of the well, and ras the springs 43 frictionally engage the casing 40 and are inhibited against rotation, the pin Si is moved to the bottom of the upper or vertical leg of the J-slot. 'Ihen the mandrel body il' may be lifted with relation to the sleeve Z7 as the springs 43 frictionally engage the casing ed to inhibit upward movement of the sleeve Z7. See Fig. 2,

Now, as iiuid is pumped down the casing 40 with the valve seat 59 of the retaining nut 31 seated on the inclined shoulder 32 of the valve element 56, the packer 29 is set against the casing 4d by virtue of the fluid pressure exerted within the cup ofthe packer, since fluid can only pass through the packer if at a pressure to pass down the longitud-inal ports 33 and radially outwardly past the shoulder 34 against the pressure of the upwardly urged valve member 35. When the pressure of the pumped fluid is built up to this degree, such pressure is ample to firmly set the packer 29 against the casing 40. Such pressure of the pumped uid is also adequate to wash through the perforations 53 above the packer into the sand forma-tion 54 and downwardly therethrough to return to the casing 40 through perforations 53 below the packer 29, and to carry the washed sand downwardly in the casing and thence upwardly through the mandrel bore i3 to the top of Ithe well bore for disposition above the closure 41.

The nut 37 has thereon friction eleme-nts or scratchers 46 for the purpose of scraping and cleaning the casing 40 and also these friction elements 46 bind the nut against rotation while the tool may be rotated, with the consequence that the nut 37 may be raised or lowered on the mandrel 1l', dependent upon the direction of tool rotation, to thereby increase or decrease the tension of the spring 36 and thereby increase or decrease the fluid pressure required to open the valve member 35. i

In lifting the tool from the position of Fig. l, the pin 51 on the mandrel 11 is lifted into the small vertical slot thereahove forming the lower tip of the J, and then the mandrel l1 and sleeve 27 are locked together against relative rotation therebetween, and in a like manner with the pin 51 in the vertical slot of the J-slot 52, as shown in Fig. 2, the mandrel il' and sleeve 27"-are locked together against relative rotation.

Broadly this invention relates to a cleaning tool operable on a tubing string in a manner that fluid circulated down the casing will set the packer thereon so that the pressurized ilu-id may then be circulated to clean the perforated casing and wash the formation outwardly thereof. The invention is not limited to the structures disclosed and described but other structures are considered as well as such may fall within the broad spirit of the invention and within the broad scope of interpretation claimed and merited for the appended claims.

What is claimed is:

l. A well screen perforation cleaner for cleaning a perforated section of a cased well bore and adapted at its upper end for connection to a pipe stem to be lowered thereon into a well, said cleaner including a hollow mandrel connected to said stem as the lowermost element thereof, a sleeve encircling and slidable upon said mandrel, means carried 'by said sleeve and connected thereto for yieldably, frictionally engaging said casing to inhibit movement of said sleeve, an upwardly facing cup-like packer encircling said sleeve and carried thereby to frictionally engage the well `bore wall, a iluid passage provided in said sleeve extending from its exterior above the connection of said packer thereto through its interior to discharge therefrom -below said connection, a valve seat on the exterior of the lower end of said sleeve outwardly of said fluid passage, a valve element carried by said mandrel and engageable with said valve seat and encircling said mandrel beneath said packer and said sleeve and having a ow passage therethrough establishing fluid communication with said fluid passage when said valve element is in seated engagement with said valve seat, means biased to normally close the lower end of said valve element flow passage, said mandrel being adapted` to be lifted with relation to said sleeve to seat said valve element on said valve seat to place said uid passage and said ilow passage in communication and said packer then being expandable into rm engagement with the well bore wall by pressure of fluid from thereabove and said -biased means then being openable by ex- -cessive iluid pressure.

2. A well screen perforation cleaner for cleaning a perforated section of a cased well bore and adapted at its upper end for connection to a pipe stem to be lowered thereon into a well, said cleaner including a hollow mandrel connected to said stern as the lowermost element thereof, a sleeve encircling and slidable upon said mandrel, means carried by said sleeve and connected thereto for yieldably, frictionally engaging said casing to inhibit movement of said sleeve, an upwardly facing cuplike packer encircling said sleeve and carried thereby to frictionally engage the well bore Wall, a fluid passage provided in said sleeve extending from its exterior above the connection of said packer thereto through its interior to discharge therefrom below said connection, a valve seat on the exterior of the lower end of said sleeve outwardly of said fluid passage, a valve element carried by said mandrel and engageable with said valve seat and encircling said-mandrel beneath said packer and said sleeve and having a flow passage therethrough establishing fluid communication with said fluid passage when said valve element is in seated engagement with said valve seat, means biased to normally close the lower end of said valve elementV flow passage, a nut threaded on the exterior of said mandrel and a spring reacting between said nut and said biased means as the means normally biasing said biased means to closed position, said mandrel being adapted to be lifted with relation to said sleeve to seat said valve element on ysaid valve seat to place said fluid passage and said ow passage in communication and said packer then being expandable into firm engagement with the well bore wall by pressure of uid from thereabove Iand said biased means then being openable by excessive fluid pressure.

3. A well screen perforation cleaner for cleaning a perforated section of -a cased well bore and adapted at its upper end for connection to a pipe stem to be lowered thereon into a well, said cleaner including aY hollow mandrel connected to said stem as the lowermost element thereof, a sleeve encirclingv and slidable upon said mandrel, means carried by said sleeve and connected thereto for yieldably, frictionally engaging said casing to inhibit movement of said sleeve, an upwardly facing cup-like packer encircling said sleeve and carried thereby to frictionally engage the well bore wall, a uid passage provided in said sleeve extending from its exterior above the connection of said packer thereto through its interior to discharge therefrom below said connection, a valve seat on the exterior of the lower end of said sleeve outwardly of said uid passage, a valve element carried by said mandrel and engageable with said valve seat and encircling said mandrel beneath said packer and said sleeve and having a ow passage therethrough establishing ud communication with said fluid passage when said valve element is in seated engagement with said valve seat, means biased to normally close the lower end of said valve element flow passage, a nut threaded on the exterior of said mandrel and a spring reacting between said nut and said biased means as the means normally biasing said biased means to closed position, said mandrel being adapted to be lifted with relation to said sleeve to seat said valve element on said valve seat to place said fluid passage and said tlow passage in communication and said packer then being expandable into iirm engagement with the well bore wall by pressure of iluid from thereabove and said biased means then being openable by excessive fluid pressure, said nut having friction means thereon engaging said casing whereby with said drill stem being connected to said pipe stem rotation ofvsaid pipe stem in-one direction may move said nut upwardly to tighten spring reaction against said biased means or whereby rotation of said pipe stem in the reverse direction may move said spring downwardly to decrease spring reaction against said biased means.

4. A well screen perforation cleaner for cleaning a perforated section of a cased well bore and adapted at its upper end for connection to a pipe stem to be lowered thereon into a well, said cleaner including a hollow mandrel connected to said stem as the lowermost element thereof, a sleeve encircling and slidable upon said mandrel, means carried by said sleeve andconnected thereto for yieldably, frictionally engaging said casing to inhibit movement of said sleeve, an upwardly facing cup-like packer encircling said sleeve and carried thereby to frictionally engage the well bore Wall, a fluid passage provided in said sleeve extending from. its exterior above the connection of said packer thereto through its interior to discharge therefrom below said connection, a valve seat on the exterior of the lower end of said sleeve outwardly of said fluid passage, a valve element carried by said mandrel and engageable with said valve seat and encircling said mandrel beneath s aid packer and said sleeve and having a ow passage therethrough establishing duid communication with said iiuid passage when s-aid valve element is in seated engagement with said valve seat, means biased to normally close the lower end of said valve element ow passage, said sleeve and said mandrel providing cooperating J-slot and pin means whereby said sleeve and said mandrel may be locked together or said mandrel may be lifted with relation to said sleeve to bring said valve element into seated engagement with said valve seat, said mandrel being adapted to be lifted with relation to said sleeve to seat said valve element on said valve seat to place said tluid passage and said ow passage in communication and said packer then being expandable into firm engagement with the Well bore wall by pressure of fluid from thereabove and said biased means then being openable by excessive duid pressure.

5. A well screen perforation cleaner yfor cleaning a perforated section of a cased well bore and adapted at its upper end for `connection to a pipe stem to be lowered thereon into a well, said cleaner including a Ihollow mandrel connected to said stem as the lowermost element thereof, a sleeve encircling and slidable upon said mandrel, means carried by said sleeve and connected thereto for yieldably, frictionally engaging said casing to inhibit movement of said sleeve, an upwardly facing cup-like packer encircling said sleeve and carried thereby to frictionally engage the well bore wall, a uid passage provided in'said sleeve extending from its exterior above the connection of said packer thereto through its interior to discharge therefrom below said connection, a valve seat on the exterior of the lower end of said sleeve outwardly of said iluid passage, a valve element carried by said mandrel and engageable with said valve seat and encircling said mandrel beneath said packer and said sleeve and having a flow passage therethrough establishing fluid communication with said fluid passage when said valve element is in seated engagement with said valve seat, means biased to normally close the lower end of said valve element flow passage, said sleeve providing a J-shaped slot therein and said mandrel providing a pin to extend into said slot whereby said mandrel and said sleeve are locked together against relative rotation with said pin in the top of the shorter, vertically extending leg of said J-shaped slot and with said valve seat spaced above said valve element or whereby with said pin posiltioned in the longer, vertically extending leg of said J-shaped slot said mandrel may be lifted with relationv to said sleeve to bring said valve element into seated engagement with said valve seat with said pin in the top of said longer, vertically extending slot and with said mandrel and said sleeve locked together against relative rotation therebetween, said` mandrel being adapted to be lifted with relation to said sleeve to seat said valve element on said valve seat to place said fluid passage and said flow passage in communication and said packer then being expandable into iirm engagement with the well bore Wall by pressure of uid from thereabove and said biased means then being openable by excessive uid pressure.

References Cited in the file of this patent UNITED STATES PATENTS 2,143,196 Knoth Ian. 10, 1939 2,562,458 Hartsell July 31, 1951 2,740,481 Arterbury et al. Apr. 3, 1956 

